Conventionally, sealed batteries are available that include a case enclosing an electrode assembly and electrolyte, the case having an external terminal and an electrolyte fill port. In such a sealed battery, the battery case serves as a terminal of one polarity, as disclosed in JP3523530B and JP3675954B, for example, and a connection member to which a lead wire is connected (i.e. a conductive connection for the positive electrode and a current extracting lead plate) is attached to the battery case. The connection member is composed of a clad material having a layer of the same metal material that forms the battery case and a layer of the same metal material that forms the lead wire. The connection member is attached to the battery case in such a way that the layer of the same metal material forming the battery case is in contact with the battery case.